Running Cars and Homes on Grass Power

There is a big effort going on to make the county energy efficient and one element of that is using ethanol to power motor vehicles . Up until now, ethanol has been made from corn and blended with gasoline. Efforts are being made to make ethanol more efficient thereby lowering the amount of gasoline that is added to the mix.

Recent developments, however, indicate that corn may not be the best choice and certain wild prairie grasses actually produce a more efficient fuel.

Switch Grass (Panicum virgatum) is a grass native to North America that is found growing wild around crop land in states like Nebraska and North and South Dakota. It has been shown that switchgrass produces five times more energy than it takes to make it grow.

Taking everything into consideration including the amount of seed and fertilizer used, the amount of fuel used to power the machinery needed to farm it and the amount of grass harvested, the results show that ethanol made with switchgrass produces 540 percent of the energy that is used to produce it. Corn delivers only 25 percent more than the energy used. That is a very significant difference and a good indication that switchgrass has a big future in the fuel business. Of course variables such as the amount of rainfall and the time of year the rain falls can effect the crop, but still there will be a big difference.

Giant Miscanthus (Miscanthus x giganteus), is a hybrid grass that grows up to 13 feet high. It is not the grass itself that is used to make fuel, but the bamboo like stems that remain after the leaves drop off in the winter. The stems are used as a replacement for solid fuels such as coal. Miscanthus removes carbon from the air as it grows. When it is burned as fuel, it replaces the exact same amout as it removed, meaning it does not have a negative effect on the carbon dioxide levels. Researchers in Illinois estimate if 10 percent of the land in the state was used to produce Miscanthus, it could provide 50 percent of the electricity used in the state.

Using grass instead of corn has another advantage. One of the arguments against using corn is the fact that it is a food crop for people and farm animals and using it for fuel cuts back on the amount available. Not so for the grasses.

Illinois State University

Scientific American

Energy Refuge